Greater London · England
Window Mastic in Bankside
Our applicators work in Bankside on mastic around window and door frames, sills and patio doors. Old material cut out, joints cleaned and sealed neatly and a 12-month guarantee.
- Gaps left after new windows were fitted
- Hard, cracked sealant around windows
- Draughty joints inside around the window
How to look after the new joints
Joint life depends on how it’s used and looked after. We suggest:
- Look round the frames every year or so
- Clear any debris from frame drain holes
- Clean frames with a soft cloth and soapy water
- Paint up to the joint, not over it
Wipe the frames with soapy water when you clean the windows, and avoid solvent cleaners on the sealant.
Signs to watch for: cracks in the mastic, gaps you can see light through, damp on the reveal or mould around the inside of the frame. Any of these is worth a call.
About our window mastic in Bankside
Whether it’s one leaking patio door or every frame on the house, the work is priced before anything is done. To get one, phone 0345 464 0079 or email us with the number of frames and any access details. If you’re dealing with a bead that doesn’t match the frame and untidy mastic left by window fitters, we can put it right.
London has a lot of flats and conversions, where windows are often on upper floors. In a converted house or block, the lease usually says who is responsible for the windows, so it’s worth checking before booking, and access in Bankside is something to talk through when you book.
You are covered for a year from the day we finish. If anything is not right with it, call 0345 464 0079 or drop us an email.
- Location
- Bankside (SE1, EC4Y, EC4V)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Price
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Leave it or put it right?
A quick bead over the top of old mastic looks like an easy fix, but new sealant cannot bond to old, crumbling mastic. It soon lifts and the leak carries on behind it. The old mastic has to come out. In older London homes, water behind a failed joint soaks into brick and timber without much sign, and once it shows in Bankside, the repair is bigger than a sealant job.
A failed joint rarely gets cheaper to fix by waiting, because water and mould keep working on it. If you are unsure, call 0345 464 0079 or email us for an honest opinion and a quote.
Why choose Mr Mastic in Bankside
- More than 20 years in sealant work
- Rated 4.9 stars on Google
- 12-month guarantee on every job
- ARBOMaster approved applicator
See our cost guide and customer reviews.
DIY versus a professional finish
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
A DIY attempt doesn’t rule out a professional job. We cut it out and start again, so just mention it when you contact us.
Your questions about window mastic in Bankside
Can you do window mastic in Bankside?
Yes. We work across London and the South East, and Bankside is part of that. Just ring 0345 464 0079 or email us with a few details of the job.
I let a flat near London Blackfriars station. Can you help?
Yes, rental work is part of what we do. Just call 0345 464 0079 or send us an email and tell us about the property, and we’ll give you a clear quote.
Is the work guaranteed?
Yes. Our one-year guarantee covers every job.
What do you put in the joint?
It depends on the joint: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. Brands we use include Arbo and Everbuild.
Are you fully insured?
Yes. Full insurance covers our work.
How long before the joint can be used?
Cure times vary by product and the conditions. We tell you how long to leave it before we go.
Where are you based?
We’re based in Crawley, West Sussex, and we work across South East England, London and Scotland.
Do you seal inside as well as outside?
Yes. Plenty of draughts come through the inside joint as well as the outside, so sealing both is often worthwhile.
Nearby places to Bankside
Other services in Bankside
What happens on the day
We work through the job in order: protect, prepare, seal, tidy. For most jobs that takes anything from an hour or two to a full day, depending on how many frames there are. In Bankside, flats, stairs and shared entrances are part of the routine. If the building has a concierge, managing agent or access rules, tell us when you book.
- Each frame is looked over and we agree which ones need resealing.
- We remove the old mastic and clean the frame edge and wall.
- Deep gaps get closed-cell backing rod to set the depth.
- A flexible exterior sealant is applied in a colour to suit the frame.
- We tool each bead neatly and check every joint is closed.
Getting ready for the visit
- Keep children and pets away from the work area
- Where the joints are inside, avoid wetting them before we arrive
- On commercial sites, let us know about site rules
Getting a quote
We quote each job on its own, so start by telling us what you need. Just call 0345 464 0079 or email us with the details, and photos are welcome.
Read more
Windows and doors in Bankside
London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Historic houses like Mansion House (about 0.6 miles north-east) are a reminder that the area around Bankside has older buildings as well as new. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic.
Letting a property close to London Blackfriars station? Then renewing tired window mastic between tenants heads off draught and damp complaints. For an older house near a landmark such as St Mary Mounthaw, the joint between an old wall and a newer frame is normally the first place rain gets in.
Bankside is about 1 mile north of London, in Greater London. For window mastic in and around Bankside, please call 0345 464 0079 or email us for a quick quote. We cover Greater London from our Crawley base, Bankside included. 764 places in Greater London are on our list, from the larger towns to small villages.
Here we cover the SE1, EC4Y and EC4V postcode area for window mastic. Local streets include Bear Lane, Bush Lane and Swan Lane. Being close to the A201 and A300, Bankside is easy for our applicators to reach. Nearby, we also carry out window mastic in Blackfriars (1 mile north-west), Temple (1 mile north-west), Temple Bar (1 mile north-west), Waterloo (1 mile south-west) and Smithfield (1 mile north). Within a short drive, we also cover Kensington (4 miles west), Walthamstow (6 miles north-east), Hampstead (5 miles north-west), Ruislip (14 miles west), Brompton (3 miles west) and Stockwell (3 miles south).
Near you in Bankside
Around Bankside, our work takes us to homes and buildings near St Mary-at-Hill, Bernie Spain Gardens and St Andrew's and St John's Church of England Primary School. Nearby too are Barts Health Archives (0.6 miles north), The Cathedral School of St Saviour and St Mary Overy (0.5 miles south-east) and Founders Arms (within half a mile west). Bankside has its own railway station: London Blackfriars station. A little further out are Royal Waterloo Hospital for Children and Women (0.6 miles west) and Gabriel's Wharf (under half a mile west). Green spaces nearby include Ludgate Hill and Barnsbury Wood.
What we are called out for in Bankside
Frames are never completely still. Sun on a frame makes it expand, and it contracts again overnight, while the masonry beside it stays put. If the sealant can’t stretch, it splits.
These are the problems we’re asked about most:
- Cracked sealant at the sill ends
- Draughty joints inside around the window
- Mastic that has split away from the wall
- Water coming in at the bottom corners of a door
Bankside is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
What to look for in a quote
- When the joint can take water or movement
- How hidden problems are handled
- Whether you can choose the colour
- Is the old sealant removed completely?
Different surfaces, different methods
uPVC windows
uPVC expands and contracts noticeably with temperature, so we use a flexible, low-modulus sealant. White is the usual colour, with brown, anthracite grey and black for coloured frames.
Patio & French doors
Not every patio door leak is a mastic problem: blocked drain slots, worn brush seals and threshold details can let water in too. We check before we reseal.
How we quote for window mastic
The quote reflects the job in front of us. We look at:
- Whether the work is at height
- How many areas need sealing
- The product the joint needs
- Mould in or behind the old joints
Doing several joints on one visit normally makes better use of the time than several visits. You will get one clear quote for the whole job.
Helping us quote
When you call or email, it’s useful to know:
- Where the property is
- What’s wrong with the joints now
- Whether it’s a home or a business
- The rough size of the job
There’s no standard price list, because every job is different. Instead, we give you a clear price for your job. To arrange one, ring 0345 464 0079 or send us an email.